Severe Thunderstorm Warning 207, NWS Grand Forks, ND

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
250 PM CDT THU AUG 13 1998

FORECAST CHALLENGE THIS PERIOD WILL BE TSRA CHANCES AND INTENSITY AS
WELL AS TEMPS. MODELS IN FAIR AGREEMENT THIS PERIOD WITH ETA COMING
AROUND TO STRENGTH OF COLD FRONT DEPICTED BY NGM YSTDY ALTHOUGH STILL
NOT AS COLD. H5 SHORT WAVE/VORT MAX PUSHING ACROSS FROM CENTRAL MB TO
SOUTHERN SASK INTO NW CORNER OF ND WITH 40 METER HEIGHT FALLS AT 500
FROM 12Z UA PLOTS. W-E BAND OF DARKENING ALSO SHOWING UP ON WV LOOP JUST
NORTH OF ND BORDER. ON SFC MAIN COLD FRONT FROM WEST OF LAKE YWG
SOUTHWEST TO NORTHEAST MONTANA. OVR FA SFC FLOW WEAK WITH SEVERAL WK
BOUNDARIES. WK BOUNDARY RUNS FROM NR INL TO FAR AND ALONG ND/SD BORDER
TO SFC LOW OVR SW ND/SD BORDER. ANOTHER DEWPOINT BOUNDARY CONTINUES
ALONG ND/MN INL BORDER AREA WITH SMALL CU FIELD DEVELOPING IN THIS AREA
ATTM. OTHER LESS DISCERNABLE BOUNDARIES POSSIBLE LEFT OVER FROM PREVIOUS
CONVECTION. AIRMASS FAIRLY UNSTABLE HOWEVER MOIST CONVERGENCE WEAK ATTM
AND AIRMASS CAPPED FROM ADAP. WITH WK BOUNDARIES INPLACE CHC OF
CONVECTION IS ALLWAYS THERE. WITH CAPPING MAY HAVE TO WAIT TILL
STRONGER COLD FRONT AND MID LEVEL COOLING APPROACHES AND INTERACTS WITH
WK BOUNDARIES IN PLACE. EVEN THOUGH STRONGEST MID LEVEL AND JET
DYNAMICS REMAIN NORTH OF BORDER STILL FEEL THERE IS A RISK FOR A FEW
SEVERE STORMS CONSIDERING PAST FEW DAYS. FRONT SWEEPS THROUGH FA
OVERNIGHT AND WITH INCREASING BAROCLINICITY FRONTOGENETIC FORCING
INCREASES ALONG WITH LOW LEVEL MOIST CONVERGENCE. AS MENTIONED EARLIER
BOTH MODELS INDICATE HEALTHY CAA WITH THE NGM THE STRONGEST. LOOKING
UPSTREAM DEWPOINTS FALL TO THE MID TO UPPER 50S WITH COOLEST READINGS
BACK INTO ALBERTA. COOLEST TEMPS TONIGHT FROM NW TO SE WITH ABOVE
MENTIONED DEWPOINTS AS A PLACE TO START. MOS AND FAN TEMPS PRETTY CLOSE
AND WITHIN ABOVE THINKING.

FOR DVL...PARTLY CLOUDY WITH WIDELY SCATTERED EVENING
THUNDERSTORMS...SOME COULD BE SEVERE. COOLER WITH A LOW 55 TO 60. WIND
BECOMING NORTHWEST 10 TO 20 MPH.
GFK...PARTLY CLOUDY WITH WIDELY SCATTERED THUNDERSTORMS...POSSIBLY
SEVERE THIS EVENING. LOW AROUND 60. WIND BECOMING NORTHWEST 10 TO 15
MPH.
FAR...BECOMING PARTLY CLOUDY WITH WIDELY SCATTERED THUNDERSTORMS
DEVELOPING...A FEW COULD BE SEVERE THIS EVENING. LOW AROUND 60.
WIND BECOMING NORTHWEST 10 TO 15 MPH.
MN4-6>7-9>13-16>22-23
.TONIGHT...BECOMING PARTLY CLOUDY WITH WIDELY SCATTERED EVENING
THUNDERSTORMS...A FEW POSSIBLY SEVERE. COOLER WITH A LOW FROM 55 TO 60.
WIND BECOMING NORTHWEST 5 TO 15 MPH.
MN17>24>27-32>40
.TONIGHT...BECOMING PARTLY CLOUDY WITH WIDELY SCATTERED THUNDERSTORMS
POSSIBLE...A FEW COULD BE SEVERE THIS EVENING. LOW IN THE LOWER 60S. LT
WIND BECOMING NORTHWEST 5 TO 15 MPH.
VOELKER

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052-053-130600-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
555 PM CDT WED AUG 12 1998

...ISOLATED SEVERE THUNDERSTORMS EXPETED TO CONTINUE INTO EARLY EVENING...

A WEAK COLD FRONT WILL APPROACHING THE INTERNATIONAL BORDER HAS COMBINED
WITH MODERATE INSTABILITY TO PRODUCE ISOLATED SEVERE THUNDERSTORMS.
AFTERNOON TEMPERATURES NEAR 90 AND DEWPOINTS IN THE UPPER 50S TO MIDDLE
60S ALONG AND JUST BEHIND THE FRONT HAVE COMBINED WITH THE FRONT TO SET
OFF THESE ISOLATED SEVERE STORMS. CONDITIONS WILL REMAIN FAVORABLE INTO
THE EVENING HOURS. THE BEST THREAT FOR SEVERE WEATHER WILL MAINLY BE
BETWEEN U.S. 2 AND THE CANADIAN BORDER THROUGH SUNSET. WHILE LARGE HAIL
IS THE MAIN THREAT...DUE TO THE SLOW MOVEMENT OF THE STORMS LOCALIZED
FLOODING IS LIKELY AS WELL.
EWENS